Catalyst and preparation thereof



V preferablyusinfgsuclj: proportions andf to maintain'a small excessoffre CATALYST Alo' PREPARATION THEREOF Charles W; Seelbach, Cranford,: and William John Gilbert McCulloch, Plainfield, N.J., assignors to Esso' Research and Engineering Company; a corporation of Delaware No Drawing. ApplicationAprilz, 1956 Serial Nassau 1 7. clams. (Cl. 252-429 This invention relates to the preparationof a-novel type of catalyst, andjsto special methodsfof preparing same" and using it for-various chemical reactions;

*The

accord-ing to-thefollowiri chemiealreactions: it, y i itet z-ia s t eactedqtitanium,

then reacting-the. resulting f'ca taly w' h metal compound.suchv as aluminumetriethy nv ion aybeit n i y p par it a y t erably. filtered to remove any TiCL; liquid, and

2 I i p then Washed witha suitable inert liquid such as normal .hep-

tane. v

The resultant high temperature metal reduction product of the reducible titanium chloride, is then preferably ground to a powdenor otherwise comminuted, to a suitable state offineness, e.g. preferably finer than mesh anorganic e se ing catalyst is foundexceedingly eiiectiv for carrying? out the polymeriiation' of, unsaturated compounds, [par-' tieularlyalpha .olefins such aspropylene. 7-; z a

' 15K313 is. known to .exist in several for'ms; E ;For instance, if-TiClis reacted with hydrogeniin" the presencetof, a.

solidv electric discharge, .TiCl is produced --a brown amorphous form. Also, {litis known that this brown.

amorphous TiCl may be converted by heating at 200 C. toproduce a violet-coloredcrystalline form of V 'ljicl It is also known ,that at very-high temperatures su'chas 40 0.47() C., TiCl may disproportionateinto TiCl and TiCl It has also beendisclosed in theiliter'a mm that some TiCl may be made according tothelequa- V e to a substantially higher temperature, in the-range of 35060 0 C., preferablyabout,400500 C. The pres- V surem'ay be from about-f5, to I00 atmospheres, preferably about 10 to 50 atmospheres, and the time of, reaction may be varied from about lchourto 1,000 hours,'preferably about'l0rto500 hours. litotlrjthepressurev and time vary, inversely according Ito the temperature used. The

reaction is preferably carried "out in a suitable pressure vessel such as. an autoclave, and this is preferably providedwith means for agitation during the reaction.

The proportions of materials to be used 'may vary as desired within the approximatejlimits of aboutOJS to 2.0-mols, preferably about 08; to 1.5' mols :of Ti, per

3-,mols'of lTiCl and the reaction is either carried out to the complete reaction of all of the Ti, or preferably only torsuch eXtent as-to leave aniexcess of titanium in therange'of 0;l to 1.0 mol of titanium per 4 mols; of

TiCl v v 11 After extent; the reaction vessel is'cooled, and the re action mass,

.which is essentially a,granul ar solidfmassfwhichmay;

" contai1 1fsomefree unreacted titanium chloride liquid, and

some free titaniumpowdr; or, titanium atoms, is'prefthe reaction hasibe'en'carried out to the'desired an forth,

per ;linear inch,-and preferably between about 100 mesh and,500 mesh. 'The resulting powder is then added to about'j'5l00 partsby weight of a suitable liquid such as normal heptane,and itis activated by addition of an organoz-metal compound, such as aluminum *triethyl, or

aluminum diethyl monochloride,'preferably added insolution'in a similar solvent suchas normalYheptme'. aIn

eifecting thisac'tivation a'n Al/Ti molarratioof 0'.1'to a e ,l0.',0 may b e used,- preferably about -1-5, eig'; l-Sinolspoff aluminum'triethylper moli'of- 'high;.temperatureTireduc tion'productof, 'IiCl calculated though it;fmay:.containt'some"free 0 only partially corn- 'bin'ed -Ti, "Catalystfslurry'may beithen either'used di 9 L 4 l, I rectly for promoting various chemical-reactions such as r reaction conditions Pbly neri ionr 1 if desired the catalyst slurry, may be agitated for .a p

cd 'for catalyzing. o-ri pro -The principles 'of this invention may begapplied not only to} the reduction'of ,TiCl; to .TiCl but'aljso the fur: ,thenreduction of TiCl toTiCl 'acco'rding to'gthe equacording to the equation a w e TiClfl-Ti-ZTiCl *In eachl case, however, it is preferable to use a suffi cient excess. of thettitaniumto have about 0.1 to 1.0 mol of titanium present in the finalproduct per mol of the;

reduced titanium chloride. As an additional guide in carrying out this invention, it may'be stated that regardless of the number of chlorine atoms presentin the'starb' ing titanium chloride", and regardless of theproportionsof titanium chloride and. titanium used, it is preferable that the final reduced product contain an excess of about preferably y-'ab out -l2%',' preferably about l- 5-25 of titanium, by weight.

V In carrying out thisinvention it ispossible to usef f other titanium halides or other'titanium compounds such 1 as ,TiBr Ti Cl '(OCl) titanium acetyl 'ac etonate hydrated oxide, alcoholates, etc.,tor mixed compounds such as TiCl (OCH Also, more broadly, the invention I may be applied by using in place of'titanium compounds, I corresponding compounds of other. transition metals of groups IV (b), V(l and VI( b) of theperiodie table, inclridingfor'instanceZr, Hf,' V, Nb, Ta, Cr, Mo and W. V Certain other'transition heavy metals; of groups VII(b) and" VIII may be used'such as manganese and iron comj i J i V "The, catalysts of proportion of a free or substantially 'unre'acted eriodjof time of from l-rmin'. to an hour "r,-so,liat"room.tem'peratureor slightly elevated rtempera-- V the present invention comprise a" major proportion of. an at least partially reduced metal" 7' compound of a transition heavy metal-of groups IV,(b'), e .7 V( b YI(b), VII(b) and VIII of the periodic table, and

metal chosenfrom the above groups. The partially reduced'metal compound of a transition heavy metal of groups IV(b), V(b), VI(b), VII and VIII of the periodic table is a transition heavy metal compound wherein the transition heavy metal is present as the cationic component of the compound and is in a lower valence state than its highest possible oxidized valence state.

Instead of using individual compounds, one may use mixtures of two or more difierent materials such as TiCl and ZrCl and it is not necessary that the metal used for reducing the TiCl be titanium, but may be any one of the other heavy metals listed above, or mixtures thereof.

The organo-metal compound to be used in activating the reduced heavy metal halide may be an aluminum trialkyl, which may have 1 to 20 carbon atoms, preferably 2 to 12 carbon atoms in the alkyl groups, and these alkyl groups may be either like or unlike; or one may use various aluminum dialkyl mono-halides, e.g. aluminum diethyl mono-chloride, aluminum diethyl mono-bromide, aluminum dimethyl monochloride; or other substituted aluminum alkyl compounds such as aluminum dimethyl methoxy; or various other derivatives having the general formula AlR X, where X may be a secondary amine, acid amide, mercaptan, thiophenol, carboxylic acid, etc.; or,

more broadly, one may use other reducing' compounds of metals of the second and third-groups of the periodic table such as zinc and magnesium hydrocarbon halides, or zinc and magnesium dialkyls, or corresponding aryl compounds; or any of these compounds together with an alkali metal or alloy, or an alkali metal hydride.

In preparing catalysts according to this invention, all steps should be carried out in the absence of moisture, and preferably also in the absence of oxygen or other harmful impurities. This may be done readily by blanketing the materials with an inert gas such as nitrogen. The

raw materials, i.e. both the reactants and inert liquids, etc. may be preferably purified or otherwise treated to remove traces of moisture, oxygen or other impurities.

The details and advantages of the invention will be better understood by a consideration of the following experimental data, which are given for the sake of illustration but without intention of limiting the invention to the specific materials and conditions.

Example I.-Titanium powder (12.5 grams containing 20% added moisture) is heated in a 300 ml. Aminco microbomb to vaporize the moisture which is vented with nitrogen. The bomb is heated to 100 C. for 2 hours, 150 C. for 1 hour and 190 C. for 60 hours. The pressure increased from 0 p.s.i.g. to 120 p.s.i.g. during the first two hours The bomb is vented and then filled with nitrogen at 100 p.s.i.g. and vented three times. This flushing procedure is repeated at each stage in the heating. The bomb is cooled, opened in a nitrogen atmosphere and 100 grams of TiCl (58 ml) is added. The bomb is sealed in the nitrogen atmosphere, placed in a rocker and heated to 400 C. for 48 hours with shaking. The bomb is opened in a nitrogen atmosphere. The product is placed in a sintered glass filter funnel, the unreacted TiCL; filtered otf and the purple solid washed three times with dry n-heptane. This solid is partially soluble in isopropanol giving a blue solution. Addition of water to this solution results in violent gas evolution and loss of color. A small amount of black powder is insoluble. This is unreacted titanium powder.

- X-ray analysis shows that this purple solid is primarily crystalline TiCl with a small amount (approximately 15%) of unreacted titanium powder. The crystal structure of this TiCl is rhombohedral, and it is believed that in this configuration each metal ion is surrounded by six chlorine atoms (coordination number of the metal is six) and each chlorine atom is in turn shared by two metal ions except for the surface chlorine atoms, which are believed to provide a special activating influence on the surface of the solid catalyst particles, particularly after further activation by the addition of aluminum triethyl or other organo-metal compound. In the preferred embodiment of this invention, the presence of excess Ti atoms have an additional activating efiect at the surface of the solid catalyst particles. and it is believed that the presence of the excess titanium is in some manner respon sible for the very much better catalyst efiiciencies (grams of polymerper gram of catalyst) obtained than when using plain TiCl without excess Ti, or by using TiCl made by some other process than the high temperature reduction of TiCl by Ti powder.

Example II.-0.5 grams of the crystalline violet TiCl prepared in Example I, and containing approximately 15% of unreacted Ti powder, is ground to a powder with mortar and pestle in a nitrogen atmosphere and transferred to a large test tube containing 50 ml. (34 grams) of dry nheptane. To this mixture is added 10 ml. of an 0.876 molar solution of Al triethyl in n-heptane, containing about 1 gram of aluminum triethyl. The mixture is agitated thoroughly, and the resulting'slurry is then ready for use as a catalyst. The Al/Ti molar ratio of this mixture is about 2.8/1.

This catalyst was added to a 300 ml. microbomb,'

followed by injection of l20fgrar'ns of cold liquid propylene, and polymerization effected at 84 C. and 400-600 p.s.i.g. for 20 hours. Solid polypropylene was obtained.

Example-III.1.8 grams of thecrystallineTiClg made in Example I, is pulverized and slurried in 20ml. of dry n-heptane, and then mixed with 20 ml. of 0.876 molar aluminum triethyl and 10 ml. of 0.876 molar aluminum diethyl mono-chloride, and additional dry n-heptaneadded to make a total volume of SOrnI. The catalyst is now readyforuseni Example IV'.The same general procedure is used as in Example I. However, the titanium powder is used directly withoutdrying and .venting the Water vapor. Also the proportion of TitoTiCl is changed to 10 gms. of Ti powder (20% moisture added) and 121 gms. of TiCl The product from this reduction is activated with A1Et in the. same manner as in Example III using an Al/Ti ratio of 2/1.

Example V.'-The same general procedure is used as in Example I including the drying of the titanium powder. The proportions are 12.5 gms. of Ti powder (20% moisture) and 120 'gms. of TiCl The reduction is carried out at 490 C. Thelyield of product is 46% of theory. This product is activated in the same manner, asin Example III using an Al/Ti ratio of 2/1.

Example VI.-Preformed TiCl prepared as in Ex ample I is activated with AlEt Cl alone at an 'Al/Ti ratio of 2/ 1 using the general procedure of Example III. The polypropylene obtained is in the same molecular weight range, but the mechanical properties of the polymer are much different. The polymer has a lower tensile strength, a higher elongation and is a'more flexible polymer.

Example VIL-Preforrned TiCl (0.5 gms.) prepared as in Example I is added to 250 ml. of n-heptane. A solution of 0.88 MAlEt (7.2 ml.) in dry n-heptane is added and the mixture is made up to a total volume of 500 ml. with n-heptane. The Al/Ti ratio is 2. This catalyst is charged to a 3-liter autoclave after standing at room temperature for 30 minutes. An additional liter of n-heptane is added and this diluted catalyst slurry is allowed to stand at room temperature for an additional 30minutes. At the end of this period 240 grams of cold liquid propylene is injected into the autoclave and the temperature increased to C. The polymerization is complete in five hours.

Example VIlL-Repeat Example VII using an Al/Ti ratio of 0.5/1 and a total catalyst concentration of 1% on propylene. v

Example IX.-Repeat Example VII using an Al /Ti ratio of 4/1 and a total catalyst. concentration of 0.5% on propylene. v

The inajor'-p,rocess dataifor:Examples;-II-IX -is ::suml-butene under somewhat similar conditionsa-butusing a marized-in the following table:: catalyst basetlon a: plain ,TiCl -iandr; not: containing any Summary table on polymerization of propylene E a l 'f n r11 1 Iv v vr v11 1 VIII l .1):

Catalyst; 7 V

.AlA1ky1 amt; amt; AlEt; 'AlEtzCl AlEti "'AlEt: AlEt: All'llratio 2 2.5. 2. V 2 2 2 0.5 4 Concentrationlnheptane,gm./liter... '25 960- 25 '25. 25 0.9 r ,1. 8 :9 Heptene Diluent, Percent 22 10 22 122 '22 80 80- '80 Reaction Conditions: i H

Time, hours--- .40 20 20 5 3 5 356' Temperature, C 80 84 84 84 77- 80 w 80 Pressure, p.s.Lg a a, 400-600 400-600 400 000 400-600 180-115 180-80 .zoo-so Catalyst Efficiency: CimsJgm. catalyst 111 r 64 144 114 125 123 80 ymer: 1 p a k a 5 Mol. WLXlO- (Harris) 113 I82 -115 98' 145 i 145 140 Percent heptaneinsolub1e- 79- 81 x73 1 67 66' '73 L NorE.AlEt; means Al triethyl; hlEtzCl means Al diethyl monoch1oride.- V i E mp X-* 3. e a yat PIE mP-J a'nld containingsome free titanium,- isl ground' to'a .;powder Q with a mortar and pestle and 0.9 gram of thismaterial is added directly to a l -literj ,hombyin a, dry nitrogen atrnosphere. The last, traces OflPOWd?! are rinsed from the weighing bottle toth ebomb'with 10"ml.*of' dry-n hep tane.f An additional 235 ml. of dry n-heptane is added mosphere.

The bomb isplaced'in a rocker and connected to the. l-butene feed line. Approximately 250 gramsof 1-bu-' vte'ne.(Matheson CF.) is transferred to the feed reservoir which is cooled in a Dry Iceisopropanolbath. The feed reservoir is pressured with 400 p.s.i.g. nitrogen'pressure and the valve to the reactor opened. As soon as the 1- butene charge is in the reactor the rocker is started and the bomb is heated to 80 C. over a period of three hours. The pressure increases to 'a maximum of 520 p.s.i.g. After hours at 80. C. the bomb is cooled. The off bomb is filled with a solid'plug of violet poly-l-butene;

reacting with the catalyst residiie1 The polymer is cut into small pieces and refluxed in isopropanollcontaining 20 .ml. of acetylacetone for 16 hours. Th e polymer is v 1 then filtered and washed with isopropariolithreetimes t v and methyl ethylketone three'times. It is then'dried in f .yacuo at 70 C.. for. 16 hours. The white product "weighs 216.3 grams which gives a catalyst efiicienc'y of 90 'gmsjgrn. The conversion of l-bu tene is :essen-,' tially' complete since the feed s stem-hasahold-u'p "of 0 The calculated:Weightfoffthe feed is 2303m and the product isolated weighed 2l6 gms. Thisis a E substa t 'ally' quantitative... yiel error." a

Ildli two. samples of the product have intrinsic viscositiesofj 2.6 and 3.3. These correspond to molecular weights; 7 (Harris) of 130300 and "183,000 respectively; The.

highest moleculanweight obtained previously with the TiCl AlR catalysts was 100,000, but this was obtained in low yield (3 vgins/gin). The highest yield -obtained previously 'was '75'lgmJgm. and'this polymer had a molecular weight of .only 50,000; I

Ether extraction of this higher mole'culanweight product gave77% insoluble material compared t0,64%' for v the 50,000 moleculanweight material mentioned above.' L 1 Thus the poly-l-butene isfa more crystalline product.

Thus the'novel catalyst describedabove results in the; 1 production of a crystalline-jpoly&1'-butene.pf desirable T very high. molecular weight a'nd .with ,goodcatialyst eifficiency. Thus the Harri'sfobtained in ExampleX was! 130,000 to 183,00Q'comparedto a' relatively poorer mo I amples of: l l

...(1 Various metals with each metalhalide;

freetitanium, and; made by an unknown"process.v The catalyst efl iciency obtained in Example X of the present invention was 90 grams ofpolymerper gram of catalyst compared to only: 1.7- grams or polymer per gram'of' catalyst in the other process just-referredito "which produceda poly- *-butene of only 30;000 molecular weight. 7 Another pointof superiority vof the poly-l butene made with the catalyst of the present invention, is its low unsaturation. For instance the product madein ExamplejX, whichJhad .a Harris molecular weight of 7 80,000 had the very low unsaturation cts. of iodine per gram;whereas*a poly-'l-butene made by afairly similar,

polymerization process except using as catalyst Ticl' activated with diet'hylflaluminum monochloride, and whichirhad a Harris molecular weight of -about 30;000, had a very much higher unsaturation of 6.61 cts. of

iodine per gram.

' Additional :examples, without experimental confirmation Example Xl.--Preparation of 'ZrCl from ZrCl; and -Zr (powder) using the general technique of Example I. gas is measured at 10 liters and the bombopened. The 4 The reaction should be carried out at about 600 C. to

'obtaingood yield. 1

7. Example XIl. Activation of ZrCl by the method of 7 Example. II; E

ofExample II- Thesexcombinations could be varied to include ex- (2) Mixtures of metals and/0r metal halides;

within experimental (3 )-'Activation or each reduction product with various "iAlRgl'or "other metal alkyls; f

W cen propylenc/heptane ratios and Al/Ti ratios. V v

. 'Exqmple X V.Prepar ationof vcl from .VCl; and/ s or VCL; plus'V, Ti 'etcl' at a temperature in the range 400 to 600 C. a

Example X VI .Preparation of HfCl fromHfCh plus ExamplerXVlL- -Preparation of Mocl rfromf MoClg .plus Mo, Ti etc. at a temperature in the range 400 to "It is" not intended that" the inventionbe, limited to the a r flabove specific examples of materials and reaction condi-i tionsgbutronly by .the) appended claimsiin which it is intendedftojsclaim all novelty inherent in thef'inventio'n," j; I 3 s well as allf'rnodifications' coming within the scope and lePular we 0 we p a e a J8???" of ntin 1 7 .Example; XIV.- IPreparation of fzrclj -"ricl mixture using TiCl plus Zr at 500 C; using-general technique ):lPolymerizationsusing suchcatalysts at various cata- Some oi the more pertinent examples are listed herebelow. 7

7 What is claimed is: 1. A catalyst-comprising a major proportion of violet crystalline TiCl and intimately associated therewith 7 about 1-50% by weight of Ti. I

2. The catalyst of claim 1 which contains from 5 to 25% by wt. of titanium. v y 7 H 3. The catalyst of claim 2 which contains an aluminum alkyl compound in amount sufiicient to givean Al/Ti molar ratio of 0.1 to 10.0.

4. A' catalyst comprising about 85% by weight of violet crystalline TiCl and about 15% by weight of Ti, intimately associated therewith.

5. A method of making a catalyst which comprises reducing TiCl with finely divided titanium at a temperature of 350-600 C. and a pressure of 5-100 atmospheres to obtain a product comprising a major proportion of violet crystalline TiCl containing about 525% of metallic titanium intimately associated therewith.

6. Amethod of preparing an improved catalyst which comprises reducing 3 mols of TiCl with 0.5 to2.0 mols of powdered Ti at a temperature of about 400-500 C. under a pressure of about 5-100 atmospheres, to obtain a solid product comprising a major proportion of violet crystalline TiCl having a minor amount of elemental 8 Ti intimately associated therewith, pulveriz'ing the resultant product, suspending it in inert organic liquid and adding thereto a solution of an alkyl aluminum com- 7. A method of making a catalyst which comprises reducing TiCL; with finely divided titanium at a temperature of 350 to 600 C. to obtain a product comprising a major proportion of violet crystalline TiCl containing from 1 to 50% 'of metallic titanium intimately associated therewith.

References Cited in. the fileof this patent UNITED STATES PATENTS p OTHER REFERENCES I. Organic Chem., vol. 10 0f 1945, pages 505-515. g 

1. A CATALYST COMPRISING A MAJOR PORTION OF VIOLET CRYSTALLINE TICL3, AND INTIMATELY ASSLCIATED THEREWITH ABOUT 1-50% BY WEIGHT OF TI.
 5. A METHOD OF MAKING A CATALYST WHICH COMPRISES REDUCING TICL4 WITH FINELY DIVIDED TITANIUM AT A TEMPERATURE OF 350-600*C. AND A PRESSURE OF 5-100 ATMOSPHERES TO OBTAIN A PRODUCT COMPRISING A MAJOR PROPORTION OF VIOLET CRYSTALLINE TICL3 CONTAINING ABOUT 5-25% OF METALLIC TITANIUM INTIMATELY ASSOCIATED THEREWITH. 